The present invention relates to a method for cleaning a cooking apparatus having a cooking chamber, in which at least one spray nozzle is arranged in the cooking chamber, is connectedxe2x80x94in particular in detachable fashionxe2x80x94with at least one supply line into the cooking chamber for water, cleaning agent, rinsing agent, and/or decalcifier, and is there driven to a rotational motion, as well as a device used for this purpose.
Such a method is known for example from DE 28 42 771 C2. There a spray arm, which is mounted in rotational fashion on a standpipe that can be connected to a pipeline or conduit, is used to prepare a cleaning in the cooking chamber, so that a rotation of the spray arm is forced by the reactive force of water exiting from the spray arm during the cleaning. The cleaning effect of water and/or a liquid cleaning agent can optionally be further improved, according to DE 28 42 771 A1, by the connection of a steam-generating unit, a heating element and/or a fan.
For example, in order to improve the cleaning effect it is known from DE 39 07 740 C2 to utilize the pivoting movement of a spray head for the step-by-step radial rotation of the pivot plane, which leads to three degrees of rotational freedom about a pivot point or center of motion. Alternatively, for example in DE 31 14 951 A1 the use of a multiplicity of rotatable spray arms for a thorough cleaning is proposed, again having a pivot point.
The known cleaning methods have indeed proven to be fundamentally effective, but, in particular given the use of built-in structures in the cooking chamber, such as racks having rails or the like, they leave behind spray traces, which has the disadvantageous result that dirt remains in the cooking chamber despite the use of expensive cleaning mechanisms.
From DE 42 06 846 C2, an apparatus is known for removing solid and/or liquid particles from a gas volume, in which a fan and a grease separator ring are used, whereby the grease separator ring can be arranged concentrically about the fan, in particular in order to hold a heating means at least partially within the flow silhouette or profile of the grease separator ring.
The object of the present invention is to further develop methods of this type in such a way that the disadvantages of the prior art are overcome, in particular in such a way that, given structures built into the cooking chamber, spray traces are avoided in an economical and environmentally friendly fashion.
According to the invention, this object is achieved in that the pivot point of the rotational motion is moved through the cooking chamber in a cyclical fashion.
It can thereby be provided that the at least one spray nozzle is moved about the pivot point with at least two, and preferably three, degrees of rotational freedom, and is moved through the cooking chamber with at least one degree of rotational freedom of the pivot point.
According to the invention, it is preferable that the at least one spray nozzle is moved through the cooking chamber along a random trajectory, stochastically, in pulsed fashion, and/or with varying speed.
In addition, it can be provided according to the invention that the motion of the at least one spray nozzle is driven via variations in the liquid pressure, preferably without auxiliary energy.
It can also be provided according to the invention that the at least one spray nozzle is connected, in particular in detachable fashion, with at least one supply line into the cooking chamber for water, cleaning agent, rinsing agent, and/or decalcifier, whereby, as soon as the least one spray nozzle is brought into effective connection with the at least one supply line, extending preferably only a cooking chamber cleaning can be set.
In addition, it is inventively proposed that it be automatically prevented that cleaning agent, rinsing agent, and/or decalcifier penetrate, individually or in combination, into the water supply of the cooking apparatus.
According to the invention it is preferred that at least one additional spray nozzle is arranged in the cooking chamber and/or fan chamber for the spraying of water, cleaning agent, rinsing agent, and/or decalcifier.
A preferred further development of the invention is characterized in that during the cleaning a fan outside the cooking chamber is switched on, and sprayed liquid is circulated inside the entire cooking apparatus.
It can thereby be inventively provided that the circulation of the liquid is supported by at least one air guide plate or spoiler, preferably acting as a nozzle and/or as protection against atomization due to contact with a heating means.
In addition, it is inventively proposed that steam and/or hot air be introduced into the cooking chamber, preferably in a controllable fashion.
A specific embodiment of the invention is characterized in that first a cleaning program is selected and is then started, whereby the following cleaning steps can be carried out in succession:
a) steaming, preferably with fan switched on;
b) introduction of a cleaning agent, preferably with fan switched on;
c) action of the cleaning agent, preferably with fan switched off;
d) clear rinsing, in particular with water, preferably with fan switched on;
e) introduction of a decalcifier, preferably with fan switched on;
f) action of the decalcifier, preferably with fan switched off;
g) clear rinsing, in particular with water, preferably with fan switched on; and/or
h) drying, in particular with hot air, preferably with fan switched on;
whereby a steaming can additionally be carried out during at least one of steps b) to g).
It can thereby be provided that the steps a) to g) can be repeated, individually or in groups, according to the degree of soiling.
In addition, it is an object of the present invention to provide a means or device for carrying out an inventive method.
This object is achieved according to the invention in that a cleaning means can be connected, preferably in a detachable and/or lockable fashion via a mount, to a wall of a cooking chamber in the area of a supply line for liquid, in particular water, and comprises a spray head system that can be lifted or, respectively, lowered relative to the mount and/or can be moved rotationally.
In addition, it is inventively proposed that at least one contact can be actuated by connecting the cleaning means, such as a reed contact via a magnet, and the contact is connected with a cooking apparatus control unit, in order to switch between the ability to activate cooking programs and cleaning programs.
It can also be provided according to the invention that the spray head system can be moved via water pressure and gravity.
Alternatively, it can be provided according to the invention that the spray head system is attached to the mount via a spray arm, in particular in the form of a parallel guide, whereby the spray arm can be moved hydraulically in a rotational fashion relative to the mount.
It is thereby preferred according to the invention that the spray head system includes a spray head mount that is attached in a rotationally movable fashion to the at least one spray arm with at least one degree of rotational freedom, and includes at least one spray head having, respectively, at least one spray nozzle, whereby the at least one spray head can be a rotary stream spray head, for example having deflection plates for pulsed rotational motion.
According to the invention, a plurality of spray heads can be attached to the at least one spray head mount, whereby the center of gravity or center of mass of the spray head mount together with the spray heads preferably represents a pivot point having at least two degrees of rotational freedom.
An inventive means or device can for example be constructed as follows:
The cleaning means can be locked to the wall of the cooking chamber by means of the mount via a plug connection, a snap connection, or the like.
The spray head system can include a turbine that can be driven via a liquid, preferably with a planetary drive.
The at least one spray head can be a rotary stream spray head, preferably having small deflection plates for pulsed rotational motion.
The hydraulics for the spray arm can include a container and a piston that can be moved therein, linked to the spray arm via a connecting rod, preferably having switching cams, and that can be controlled via at least one valve. A first valve can thereby be provided for controlling the liquid pressure in a line between the supply line and the spray head system.
In addition, a control system for controlling the liquid pressure on the piston in the container can be provided. Such a control system can include a second valve that can preferably be switched via a blocking system. The blocking system can in turn include a bolt or slide that can be stopped via a stop bar and that can be moved via a spring, which enables liquid to flow, via at least one duct from the supply line to the interior chamber of the container, whereby a supply of liquid to the interior of the container is blocked and a liquid runoff out of the container is opened when the piston has reached its highest position in the container relative to the floor of the container. The position of the piston can thereby be modified in cyclical fashion via an impulse piston, preferably with a memory or storage capacity, that is connected with a water supply, a valve tappet for lifting the piston, and a valve tappet for lowering the piston inside the container. In addition, a supply line system for cleaning agent, rinsing agent, and/or decalcifier can be provided that can preferably be connected optionally with the spray head system via an at least third valve.
A pressure switch should then be provided in the supply line system to the spray head system upstream from the third valve, said switch automatically terminating supply of liquid below a determined water pressure in a connection line from a water supply to the spray head system.
A pressure pump can thereby be provided between the at least one third valve and the spray head system, preferably upstream from the pressure switch. The use of a return or reflux valve that is connected with the water supply for the spray head system, preferably via an additional valve, and that is connected with the spray head system and with a ventilation unit, can also be provided. The pressure switch can thereby be arranged in the water supply line, downstream from the return valve, and preferably downstream from the additional valve.
In addition, a fan comprising a fan wheel and a fan motor, which are separated from the cooking chamber via an air guide plate having at least one suction and outlet opening, can be provided. A specific embodiment comprises an impact surface, preferably arranged essentially concentrically in relation to the center of a flow produced by the fan. In addition, a heating unit, preferably arranged at least partially in the flow silhouette of the impact surface, can be provided.
A steam-generating unit can also be provided.
In addition, a control system, preferably for coordinating the switching on and off of the first valve, the second valve, the third valve, the fan, the heating unit, and/or the steam-generating unit, can be provided. The control system can thereby be connected with an input keyboard and a display unit.
The invention is thus based on the surprising finding that in addition to a rotational movement at least of one spray nozzle having up to three degrees of rotational freedom about a pivot point, an additional movement, namely that of the pivot point itself, must take place in order to entirely avoid spray traces, in particular in the case in which built-in racks having rails are arranged in the cooking chamber.
According to the invention, the cleaning effect is thereby further improved in that it is possible to make optional use of the following: steam, in particular to dissolve or loosen dirt, hot air, in particular to increase turbulence, a fan, also for the cleaning of the entire interior of the cooking apparatus, and/or an impact surface, in particular in order to avoid an atomization of water and/or cleaning agent due to contacting a heating unit, and for the support of a turbulence.
For the protection of the environment, according to the invention a series of security measures are also provided, such as the use of a pressure switch and a return valve in order to avoid contaminating a water supply, in particular a household water supply, with chemicals required for the cleaning. For this purpose, the invention proposes an optimized water supply control system.
Finally, the inventive cleaning program provides a taking into account of the four cleaning parameters, namely temperature, time, chemistry, and mechanics, in combination with one another.
Additional features and advantages of the invention result from the following specification, in which exemplary embodiments of the invention are explained in detail on the basis of schematic drawings.